Economy
Price Economy#
The special items and the resources in the game will have a simulated economy. This means that the prices will be adjusted according to a different parameter.
Every item and resource have an own economy entity. An economy consists of a buy/sell-history and a stock/demand. The item-stock will not influence the number of items that can be bought. Same for the resource-demand. It will not influence how many resources can be sold. They are only a virtual parameter to simulate the price adjustments. Additionally, there is another parameter that determines a time range, over which the history should be analysed.
This economy basically implements a very easy form of price adjustments:
more items are bought => less stock => price highless items are bought => more stock => price low
more resources are sold => less demand => price lowless resources are sold => more demand => price highThese economies will calculate new prices after every command-execution. The prices will then be published through their corresponding events.
All prices will always be Integers.
(https://github.com/The-Microservice-Dungeon/trading/tree/main/src/main/java/dungeon/trading/economy)
Resources sell-price adjustments#
There is a calculation done, which will be changing the prices of the resources gradually every round. For the calculation only matters how many resources of a certain type were sold in the past.
newPrice = ceil(originalPrice * historyFactor)This factor is calculated as follows (if the factor is greater than or equals 1, the factor will be 1 and the price will stay the same):
historyFactor = resourceDemand / soldAmountInTimeRangeExample 1
demand = 10; sold = 15factor = 10 / 15 = 0,66factor <= 1=> price will be changed by a factor of 0,66
Example 2
demand = 10; sold = 3factor = 10 / 3 = 3,33factor > 1=> price will stay the same
Items buy-price adjustment#
Items are calculated with the above presented buy-history factor and an additional round-adjusting:
newPrice = ceil(originalPrice * historyFactor * roundAdjust)The buy-history factor is calculated as follows (if the factor is smaller than or equals 1, the factor will be 1 and the price will stay the same):
historyFactor = boughtAmountInTimeRange / itemStockExample 1:
stock = 5; bought = 3factor = 3 / 5 = 0,6factor <= 1=> price will stay the same
Example 2:
stock = 2; bought = 3factor = 3 / 2 = 1,5factor > 1=> price will be changed by a factor of 1,5
Also, Items will be more expensive in the endgame phases, when players have collected more wealth. This ensures a fair play.
roundAdjust = floor(200 * (1 / (1 + e^(-0,014 * currentRound) * 199)))